Hydraulic press



Dec. 19, 1967 E. RIBBACK HYDRAULIC PRESS 3 Sheets-Sheet 1 Filed Sept. 10, 1964 INVENTORI ERICH RIBBACK BY MW AT TYS Dec. 19, 1967 RIBBACK Y 3,358,493

HYDRAULIC PRESS Filed Sept. 10, 1964 5 Sheets-Sheet 2 FIG. 2.

INVENTORZ ERICH RIBBACK ATTYS Dec. 19, 1967 Y E. RIBBACK HYDRAULIC PRESS 3 Sheets-Sheet 5 Filed Sept. 10, 1964 INVENTOR I ERICH RIBBACK 91W m OE ATTY$..

United States Patent 3,358,493 HYDRAULIC PRESS Erich Ribback, Unterrn Bocksberg, Wasserbillig, Luxembourg Filed Sept. 10, 1964, Ser. No. 395,516 Claims. (Cl. 72-407) This invention relates to improvements in hydraulic presses and particularly to presses with jaws supporting the forming tools and which jaws are movable toward and away from each other. These presses are used for the reducing of tubular ends. In the heretofore known constructions these jaws are operated by a piston which moves in a cylinder in opposite directions by a pressure medium. These jaws are usually disposed at the rod of the working piston. It is also known that the jaws are connected with this rod of the working piston by transmission means. These known constructions are complicated and require very large, very powerful pressing means. The known presses cannot be arranged directly at draw benches or similar machine tools because their construction does not make possible such a configuration.

An object of this invention is to construct an hydraulic press of the above described type in such a manner that the space required therefor is compact in overall dimensions. For this purpose double-armed levers are pivoted to the press frame for pairwise movement toward and away from each other, and pivotally disposed concentrically around the Working piston. These levers support the jaws and thus the tools at their short arms the levers comprise adjacent long-press actuating arms extending in like direction and short arms extending in opposite direction from said long arms and are operated by the working piston at their long arms.

In the accompanying drawings the subject of the invention is shown schematically:

FIG. 1 shows the press in a side view;

FIG. 2 shows the subject of FIG. 1 in front view; and

FIG. 3 shows the subject of FIG. 1 in a plan view.

As is shown in the drawings a number of double-armed levers are pivotally disposed concentrically around the press and about their axes of rotation 1. The short arms 2 of the levers mount the jaws and forming tools 3 which are movable toward and away from each other-the forming tools may be cutting tools. it is a feature of the invention that the long arms 4 of the levers are operated by a working or drive piston 5 which moves in opposite directions in its working cylinder 6, the piston and working cylinder comprising an hydraulic driving mechanism positioned between the pairs of levers adapted to engage and separate the long arms 4.

The long arms 4 of the double-armed levers upport wedge-shaped cams 7. The wedge-shaped surfaces 8 of the cams 7 are built as sliding surfaces for rollls 9 which are fixed to the piston 5 by a radially extending yoke 19 the yoke 10 is in pressure contact with each pair of long arms 4 through the rolls 9 thereon. With movement of the piston 5 out of its cylinder 6 the rolls 9 roll on the wedge-shaped surfaces 8 of the cams 7. This motion causes the long arms of the levers to pivot apart and the forming tools 3 to move toward each other. The long arms 4 of the double-armed levers are spring-loaded by compression springs 11. These springs 11 move the long arms of the double-armed levers back toward each other so that the forming tools return to their first position and form an open mouth thus, there is provided spring-return means to draw the long arms toward one another. As shown in FIG. 1 the cylinder 6 carries a counter-support 21 for the spring-return means 11.

It is another feature of the invention that the wedgeshaped cams 7 are adjustably fixed in longitudinal direction of the long arms 4. Therefore the Wedge-shaped cams 7 can present staggered opposite surfaces. Therefore the long arms of the levers 4 are pivoted by the rolls 9 of the moving piston 5 not at the same time but one after another. Using the structure of the invention, therefor it is possible, by way of example, for two opposing forming tools 3 to lead and deform a tubular end into an eight and subsequently two other opposing forming tools 3 to lag and effect the folding.

The arms 2 and 4 of the levers can be constructed-in a simple manner-for each length-ratio. This ratio is improved by the inclination of surfaces 8 of the wedgeshaped cams 7 so that the force of the piston 5 can bear directly against the working piece by means of the arms 2, 4 of the levers. This structural arrangement for transmitting the force makes possible the folding of the tubes by an arrangement operated with air pressure. These circumstances make possible the manufacture of the press at a very economical price. It is possible to place a press according to the invention at each drawing machine so that transport of tubes from the drawing banks to the reducing machines can be kept to a minimum. It is also a feature of the invention that the press can embody a greater or lesser number of levers than as it is shown in the drawings. The press can be used in a simple manner, for example, with two levers as pneumatically operated tongs for clamping, cutting or other similar tasks.

What I claim is:

1. An hydraulic press comprising a press frame, a pair of double-armed levers pivoted to the press frame for pairwise movement toward and away from each other, said levers comprising adjacent long press-actuating arms extending in like direction and adjacent short arms, extending in opposite direction from said long arms, an hydraulic driving mechanism positioned between said pair of levers adapted to engage and separate said long arms, and having a cylinder therein, a radially-extending yoke fixed to the outer end of the piston rod of the hydraulic driving mechanism for axial movement therewith in pressure contact with the pair of long arms to separate said arms, a counter-support mounted on the cylinder of said hydraulic driving mechanism, and spring return means to draw the pair of long arms toward one another carried by said counter-support.

2. An hydraulic press comprising a press frame, a pair of double-armed levers pivoted to the press frame for pairwise movement towards and away from each other, said levers comprising adjacent long pressactuating arms extending in like direction and adjacent short arms extending in opposite direction from said long arms, cutting tools mounted upon said short arms, an hydraulic driving mechanism positioned between said pair of levers adapted to engage and separate said long arms and a radially extending yoke fixed to the outer end of the piston rod of the hydraulic driving mechanism for axial movement therewith in pressure contact with the pair of long arms to separate said arms.

3. An hydraulic pres-s comprising a press frame, a pair of double-armed levers pivoted to the press frame for pairwise movement toward and away from each other, said levers comprising adjacent long press-actuating arms extending in like direction and adjacent short arms, extending in opposite direction from said long arms, an bydraulic driving mechanism positioned between said pair of levers adapted to engage and separate said long arms, a radially extending yoke fixed to the outer en-d of the piston rod of the hydraulic driving mechanism for axial movement therewith in pressure contact with the pair of long arms to separate said arms, and rolls pivoted at the radial outer ends of the yoke for rolling longitudinally outwardly of said long arms to separate said long arms.

4. An hydraulic press as claimed in claim 3, including wedge pieces disposed upon said long arms against which said rolls bear.

4 5. An hydraulic press as claimed in claim 4 in which the wedge pieces are mounted adjustably lengthwise on the long arms of said doubled-armed levers.

References Cited UNITED STATES PATENTS 229,795 7/1830 Allen 72-407 335,320 2/1886 Smith 72-404 581,147 4/ 1897 Albree 72-451 631,481 8/1899 \Vesner 72-402 1,805,282 5/1931 Hammerstrom et al. 72-446 2,011,877 8/1935 Shaff 72-407 15 LEONIDAS VLACHOS, Primary Examiner. 

1. AN HYDRAULIC PRESS COMPRISING A PRESS FRAME, A PAIR OF DOUBLE-ARMED LEVERS PIVOTED TO THE PRESS FRAME FOR PAIRWISE MOVEMENT TOWARD AND AWAY FROM EACH OTHER, SAID LEVERS COMPRISING ADJACENT LONG PRESS-ACTUATING ARMS EXTENDING IN LIKE DIRECTION AND ADJACENT SHORT ARMS, EXTENDING IN OPPOSITE DIRECTION FROM SAID LONG ARMS, AN HYDRAULIC DRIVING MECHANISM POSITIONED BETWEEN SAID PAIR OF LEVERS ADAPTED TO ENGAGE AND SEPARATE SAID LONG ARMS, AND HAVING A CYLINDER THEREIN, A RADIALLY-EXTENDING YOKE FIXED TO THE OUTER END OF THE PISTON ROD OF THE HYDRAULIC DRIVING MECHANISM FOR AXIAL MOVEMENT THEREWITH IN PRESSURE CONTACT WITH THE PAIR OF LONG ARMS TO SEPARATE SAID ARMS, A COUNTER-SUPPORT MOUNTED ON THE CYLINDER OF SAID HYDRAULC DRIVING MECHANISM, AND SPRING RETURN MEANS TO DRAW THE PAIR OF LONG ARMS TOWARD ONE ANOTHER CARRIED BY SAID COUNTER-SUPPORT. 